The present invention relates to a cylindrical cutting device, and more particularly to a cutting machine or a line milling machine in which a chisel holder or like tool is removably secured to a base carried on the machine.
As a rule, such cutting devices have a plurality of bases disposed on their surface at a uniform spacing, and form, for example, a broach-loading screw or a broach spiral. In this connection, a chisel holder with an exchangeable chisel is connected to each base or, in some bases, an appropriately fitting chisel is inserted directly without having a chisel holder as an intermediate element.
A known cutting device of this type is disclosed for example in DE 43 22 402 C2. In the disclosed device, a chisel holder includes a shaft which is introduced into a plug-in receptacle of a base, and is referred to as a plug-in attachment. To prevent the chisel holder from being pulled out, the chisel holder is secured in the base with a setscrew, which can be actuated by means of a recessed hexagonally shaped tool receptacle and which setscrew engages an assigned recess of the shaft of the chisel holder.
The above method of securing the chisel holder has a disadvantage in that an internal thread of a borehole which extends through the base, and the hexagonal recess of the setscrew which serves to accommodate a tool, are susceptible to contamination especially when a cutting operation of the cutting device creates an abundant amount of dust. As a consequence, it becomes increasingly difficult to loosen the setscrew in order to exchange the chisel holder.
The present invention is therefore concerned with the problem of providing a cutting device of the above type, for which the chisel holder or holders, or like tools, are secured in a simple manner not susceptible to contamination and, accordingly, can be loosened easily when required.